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We analyzed the occurrence and mechanisms of fusidic acid resistance present in staphylococci isolated from 59 healthy volunteers. The fingers of the volunteers were screened for the presence of staphylococci, and the collected isolates were tested for resistance to fusidic acid. A total of 34 fusidic acid resistant staphylococcal strains (all were coagulase-negative) were isolated from 22 individuals (22/59, 37.3%). Examination of the resistance genes revealed that acquired fusB or fusC was present in Staphylococcus epidermidis, Staphylococcus capitis subsp. urealyticus, Staphylococcus hominis subsp. hominis, Staphylococcus warneri and Staphylococcus haemolyticus. Resistance islands (RIs) carrying fusB were found in S. epidermidis and S. capitis subsp. urealyticus, while staphylococcal chromosome cassette (SCC)-related structures harboring fusC were found in S. hominis subsp. hominis. Genotypic analysis of S. epidermidis and S. hominis subsp. hominis indicated that the fus elements were disseminated in diverse genetic strain backgrounds. The fusC elements in S. hominis subsp. hominis strains were highly homologous to SCCfusC in the epidemic sequence type (ST) 239/SCCmecIII methicillin-resistant S. aureus (MRSA) or the pseudo SCCmec in ST779 MRSA. The presence of acquired fusidic acid resistance genes and their genetic environment in commensal staphylococci suggested that the skin commensal staphylococci may act as reservoir for fusidic acid resistance genes.

The information about disease burden and epidemiology of invasive listeriosis in Asia is scarce. From 2000 to 2013, a total of 338 patients with invasive listeriosis (bacteremia, meningitis, and peritonitis) were treated at four medical centers in Taiwan. The incidence (per 10,000 admissions) of invasive listeriosis increased significantly during the 14-year period among the four centers (0.15 in 2000 and >1.25 during 2010-2012) and at each of the four medical centers. Among these patients, 45.9% were elderly (>65 years old) and 3.3% were less than one year of age. More than one-third (36.7%) of the patients acquired invasive listeriosis in the spring (April to June). Among the 132 preserved Listeria monocytogenes isolates analyzed, the most frequently isolated PCR serogroup-sequence type (ST) was IIb-ST87 (23.5%), followed by IIa-ST378 (19.7%) and IIa-ST155 (12.1%). Isolation of PCR serogroups IIb and IVb increased significantly with year, with a predominance of IIb-ST87 isolates (23.5%) and IIb-ST 228 isolates emerging in 2013. A total of 12 different randomly amplified polymorphic DNA (RAPD) patterns (Patterns I to XII) were identified among the 112 L. monocytogenes isolates belonging to eight main PCR serogroup-STs. Identical RAPD patterns were found among the isolates exhibiting the same PCR serogroup-ST. In conclusion, our study revealed that during 2000-2013, listeriosis at four medical centers in Taiwan was caused by heterogeneous strains and that the upsurge in incidence beginning in 2005 was caused by at least two predominant clones.

Methicillin-resistant Staphylococcus aureus (MRSA) is a common multidrug-resistant (MDR) pathogen. We herein discussed MRSA and its infections in Krasnoyarsk, Siberian Russia between 2007 and 2011. The incidence of MRSA in 3,662 subjects was 22.0% and 2.9% for healthcare- and community-associated MRSA (HA- and CA-MRSA), respectively. The 15-day mortality rates for MRSA hospital- and community-acquired pneumonia (HAP and CAP) were 6.5% and 50%, respectively. MRSA CAP cases included pediatric deaths; of the MRSA pneumonia episodes available, ≥27.3% were associated with bacteremia. Most cases of HA-MRSA examined exhibited ST239/spa3(t037)/SCCmecIII.1.1.2 (designated as ST239Kras), while all CA-MRSA cases examined were ST8/spa1(t008)/SCCmecIV.3.1.1(IVc) (designated as ST8Kras). ST239Kras and ST8Kras strongly expressed cytolytic peptide (phenol-soluble modulin α, PSMα; and δ-hemolysin, Hld) genes, similar to CA-MRSA. ST239Kras pneumonia may have been attributed to a unique set of multiple virulence factors (MVFs): toxic shock syndrome toxin-1 (TSST-1), elevated PSMα/Hld expression, α-hemolysin, the staphylococcal enterotoxin SEK/SEQ, the immune evasion factor SCIN/SAK, and collagen adhesin. Regarding ST8Kras, SEA was included in MVFs, some of which were common to ST239Kras. The ST239Kras (strain OC3) genome contained: a completely unique phage, φSa7-like (W), with no att repetition; S. aureus pathogenicity island SaPI2R, the first TSST-1 gene-positive (tst +) SaPI in the ST239 lineage; and a super copy of IS256 (≥22 copies/genome). ST239Kras carried the Brazilian SCCmecIII.1.1.2 and United Kingdom-type tst. ST239Kras and ST8Kras were MDR, with the same levofloxacin resistance mutations; small, but transmissible chloramphenicol resistance plasmids spread widely enough to not be ignored. These results suggest that novel MDR and MVF+ HA- and CA-MRSA (ST239Kras and ST8Kras) emerged in Siberian Russia (Krasnoyarsk) associated with fatal pneumonia, and also with ST239Kras, a new (Siberian Russian) clade of the ST239 lineage, which was created through stepwise evolution during its potential transmission route of Brazil-Europe-Russia/Krasnoyarsk, thereby selective advantages from unique MVFs and the MDR.

Brain abscesses are occasionally associated with a dental source of infection. An unusual case of frontal lobe abscess in a nonimmunocompromised child infected with multidrug-resistant Capnocytophaga ochracea is described and confirms the pathogenic potential of this organism to cause human disease in the central nervous system.

We compared the in vitro activities of tigecycline to those of other agents against 300 nonduplicate isolates of Streptococcus pneumoniae (194 isolates), Haemophilus influenzae (60 isolates), and Moraxella catarrhalis (46 isolates) recovered from patients treated in three major hospitals in Taiwan from August through December, 2003. All of these isolates were inhibited at 0.5 mg/L of tigecycline. For S. pneumoniae isolates, 72% were not susceptible to penicillin (69% intermediate and 3% resistant) and 96% were not susceptible to azithromycin. Among the 178 isolates resistant to azithromycin, 53 isolates (30%) had the M phenotype and 70% had the cMLSB phenotype. The rate of nonsusceptibility to ertapenem, telithromycin, moxifloxacin, and quinupristindalfopristin in S. pneumoniae was 3%, 2%, 1%, and 57%, respectively. For H. influenzae, 36 (60%) were not susceptible to ampicillin, among which 31 possessed beta-lactamase. A high rate (8.3%) of H. influenzae isolates with beta-lactamase-negative and ampicillin-resistant phenotype was found. All H. influenzae isolates were susceptible to azithromycin, but 40% of them were not susceptible to clarithromycin. Ninety-eight percent (44 isolates) of M. catarrhalis possessed beta-lactamase. All three fluoroquinolones tested were highly active (MIC90or =0.12 mg/L) against H. influenzae and M. catarrhalis.

The Etest was evaluated as a possible alternative to the standard agar dilution method for susceptibility testing of nine antimicrobial agents against Flavobacterium species. In studies of 100 clinical isolates, the agreement between the MICs (+/-1 log2 dilution) obtained by the two methods was acceptable for cefotaxime, ceftazidime, amikacin, minocycline, ofloxacin, and ciprofloxacin (> 90%). Conversely, the agreement between the results obtained for piperacillin was limited (84%). The overall agreement was 92.5%.

We investigated the in vitro activity of various piperacillin and sulbactam combinations against Gram-negative bacterial isolates from Intensive Care Units (ICUs) in Taiwan. Antimicrobial susceptibility testing of 1030 bacterial isolates recovered from ICUs of nine major teaching hospitals was performed using the agar dilution method. Sulbactam was added to piperacillin either at a fixed sulbactam concentration of 4mg/L and 8mg/L or at a piperacillin:sulbactam ratio of 2:1 and 4:1. Piperacillin/sulbactam at a ratio of 2:1 or a fixed 8mg/L concentration of sulbactam had better activities against Escherichia coli , Klebsiella pneumoniae , Proteus mirabilis and Serratia marcescens than other piperacillin/sulbactam formulations. For Pseudomonas aeruginosa , piperacillin/sulbactam (2:1 or 4:1 ratios) had MIC 90 values (minimum inhibitory concentration for 90% of the organisms) of 64mg/L (>90% susceptibility) compared with 64mg/L for cefoperazone/sulbactam (68% susceptibility) and 128mg/L for piperacillin/tazobactam (82% susceptibility). For Acinetobacter baumannii , both piperacillin/sulbactam (either 2:1 ratio or a fixed 8mg/L sulbactam) and cefoperazone/sulbactam were the most potent agents. Adding sulbactam to piperacillin resulted in increased susceptibility rates among piperacillin-resistant P. aeruginosa (53–57% in either 2:1 or 4:1 ratios) and A. baumannii (38–46% in either 2:1 ratio or a fixed 8mg/L concentration of sulbactam) isolates. Results of susceptibility tests with piperacillin/sulbactam are dependent on the method used. Piperacillin/sulbactam combinations possessed better in vitro activities than piperacillin alone or piperacillin/tazobactam against P. aeruginosa and A. baumannii .

This study evaluated the in vitro activities of tigecycline, ertapenem, isepamicin, and other comparators against 861 bacterial isolates recovered from patients treated in three major teaching hospitals in 2003. MICs to antimicrobial agents were determined by the agar dilution method. High rates of oxacillin resistance (58%) in Staphylococcus aureus (60 isolates), and vancomycin resistance (21%) and quinupristin-dalfopristin non-susceptibility (39%) in Enterococcus faecium (34 isolates) were found. Carbapenems had excellent in vitro activities (or=98% susceptibility) against the 419 isolates of Enterobacteriaceae, with the MIC(50) and MIC(90) of imipenem, meropenem, and ertapenem being 0.25 and 4 mg/L, 0.03 and 0.12 mg/L, and 0.03 and 0.5 mg/L, respectively. For, Pseudomonas aeruginosa (74 isolates) and Burkholderia cepacia (21 isolates), meropenem (MIC(90), 0.25, 2, and 4 mg/L, respectively) had better in vitro activities than imipenem (MIC(90), 8, 4, and 32 mg/L, respectively) and ertapenem (MIC(90), 0.5,32, and 32 mg/L, respectively). Isepamicin had a similar activity with amikacin against all Enterobacteriaceae, Pseudomonas aeruginosa, B. cepacia, and Acinetobacter baumannii, except for C. freundii isolates in which isepamicin had an eight-fold activity better than amikacin. Tigecycline had excellent in vitro activities against all isolates tested (MIC(90),or=1 mg/L) including 14 pandrugresistant A. baumannii isolates (MICs, 1-4 mg/L), except for Proteus mirabilis (59 isolates; MIC(90), 8 mg/L), Bacteroides fragilis (60 isolates; MIC(90), 8 mg/L), P. aeruginosa (MIC(90), 16 mg/L), and B. cepacia (21 isolates; MIC(90), 16 mg/L). Tigecycline, carbapenems, and isepamicin exhibited better or comparable in vitro activities against a wide spectrum of commonly encountered bacteria than other comparator antimicrobials and may represent therapeutic options for infections due to multidrug-resistant pathogens.

The annual incidence of typhoid fever in Taiwan was 2.1-3.6 cases per 1,000,000 population from 1995 to 2002. More than 80% of 45 patients with typhoid fever treated at National Taiwan University Hospital from 1996 to 2002 had elevated serum aminotransferase levels at presentation. Ten of these patients were treated during an outbreak in Taipei County in 2002, and seven of them who did not have pre-existing liver disease developed hepatitis, which was unrelated to other aetiologies. All Salmonella typhi isolates were susceptible to extended-spectrum cephalosporins and fluoroquinolones. Multidrug resistance (intermediate resistance to ampicillin, trimethoprim-sulphamethoxazole, and chloramphenicol) was found in one (2.5%) of the 40 isolates studied. Pulsed-field gel electrophoresis analysis demonstrated a high genetic diversity among S. typhi isolates and identified a novel clone associated with the 2002 outbreak. Physicians should be alert to the possibility of typhoid fever when patients, without other gastrointestinal symptoms, present with sustained fever and hepatitis.

Summary We present a diabetic patient with necrotizing fasciitis caused by Citrobacter freundii associated with an injury from the fish fin. Two isolates recovered six days after cefotaxime treatment had a cefotaxime minimum inhibitory concentration (MIC) of 0.12 and 256mg/L, respectively, and a cefepime MIC of 0.03 and 0.25mg/L, respectively. The two isolates both possessed bla CMY-2 gene. The patient responded unsatisfactorily to cefotaxime and cefepime therapy and surgical debridement but recovered completely after ertapenem treatment for 42 days.

A recent outbreak of Streptococcus suis infection associated with the slaughter, preparation or consumption of pigs in Sichuan, China has led to concerns that similar outbreaks could occur in other Asian countries. Although the pig farming industry is flourishing in Taiwan, reports of S. suis infection remain rare. We report 2 cases of S. suis meningitis successfully treated with ceftriaxone and penicillin. Previous reports of S. suis infection from the English literature are reviewed and the clinical data of cases reported in Asian and European countries are summarized. In Europe, there was good correlation between clinical disease and porcine contact, while few cases in Asia reported this association. Meningitis remained the most common presentation of infection in both areas (84.6% and 75.2%, respectively), followed by sepsis (15.4% and 18.6%, respectively), which had a higher mortality rate, particularly for splenectomized patients. Other clinical presentations included enteritis, arthritis, endocarditis, pneumonia, spondylodiscitis, endophthalmitis, uveitis and peritonitis. Deafness was a distinct sequelae (50.5% in Europe and 51.9% in Asia) after recovery from S. suis infection, especially in patients with meningitis. Not all commercial identification systems for streptococci could offer adequate speciation for S. suis. When viridans group streptococci are isolated from patients with meningitis and sepsis, prompt and correct identification of isolates to the species level should be performed, especially in areas with a high prevalence of S. suis diseases.

This study evaluated the clinical and microbiological characteristics of 16 patients who were colonised or infected with 26 isolates of pandrug-resistant Pseudomonas aeruginosa (PDRPA; intermediately-resistant or resistant to all cephalosporins, piperacillin–tazobactam, aztreonam, carbapenems, ciprofloxacin and aminoglycosides) in a university hospital during 1999–2002. All the isolates had colistin MICs ≤4 mg/L, 19 (73%) isolates had bla VIM-3 , and 25 (96%) isolates had class I integrons ( int I). Time-kill studies for two PDRPA blood isolates demonstrated synergism for cefepime–amikacin after 24 h. Pulsed-field gel electrophoresis analysis of the isolates revealed a polyclonal nature (12 pulsotypes), although clonal dissemination of PDRPA isolates among these patients was also present.

Viridans streptococci (VS) are common etiologic agents of subacute infective endocarditis and are capable of causing a variety of pyogenic infections. Many species of VS are difficult to differentiate by phenotypic traits. An oligonucleotide array based on 16S-23S rRNA gene intergenic spacer (ITS) sequences was developed to identify 11 clinically relevant VS. These 11 species were Streptococcus anginosus , S. constellatus , S. gordonii , S. intermedius , S. mitis , S. mutans , S. oralis , S. parasanguinis , S. salivarius , S. sanguinis , and S. uberis . The method consisted of PCR amplification of the ITS regions by using a pair of universal primers, followed by hybridization of the digoxigenin-labeled PCR products to a panel of species-specific oligonucleotides immobilized on a nylon membrane. After 120 strains of the 11 species of VG and 91 strains of other bacteria were tested, the sensitivity and specificity of the oligonucleotide array were found to be 100% (120 of 120 strains) and 95.6% (87 of 91 strains), respectively. S. pneumoniae cross-hybridized to the probes used for the identification of S. mitis , and simple biochemical tests such as optochin susceptibility or bile solubility should be used to differentiate S. pneumoniae from S. mitis . In conclusion, identification of species of VS by use of the present oligonucleotide array is accurate and could be used as an alternative reliable method for species identification of strains of VS.

A rapid increase of nosocomial methicillin-resistant Staphylococcus aureus (MRSA) infection (from 39% in 1991 to 75% in 2003) and vancomycin-resistant enterococci (VRE) (from 1.2% in 1996 to 6.1% in 2003) at a university hospital in Taiwan was found. The noticeable rise of MRSA and VRE was significantly correlated with the increased consumption of glycopeptides, beta-lactam-beta-lactamase inhibitor combinations, extended-spectrum cephalosporins, carbapenems and fluoroquinolones (Pearson's correlation coefficient, P < 0.05). Minimum inhibitory concentrations (MICs) of 100 non-duplicate blood isolates of MRSA (in 2003) and of 25 non-duplicate isolates of vancomycin-resistant Enterococcus faecalis and 172 vancomycin-resistant Enterococcus faecium (in 1996-2003) causing nosocomial infection recovered from various clinical specimens of patients treated at the hospital to nine antimicrobial agents were determined by the agar dilution method. All of these isolates were susceptible to linezolid and were inhibited by 0.5mg/L of tigecycline, and all MRSA isolates were inhibited by daptomycin 1mg/L, including two isolates of MRSA with heteroresistance to vancomycin. Daptomycin had two-fold better activity against vancomycin-resistant E. faecalis (MIC90, 2 mg/L) than against vancomycin-resistant E. faecium (MIC90, 4 mg/L). Decreased susceptibilities of vancomycin-resistant E. faecium and MRSA to quinupristin/dalfopristin (non-susceptibility 25% and 8%, respectively) were found. Telithromycin had poor activity against the isolates tested (MIC90, 8 mg/L). Linezolid, daptomycin and tigecycline may represent therapeutic options for infections caused by these resistant Gram-positive organisms.

Escherichia coli strains are among the major bacterial causes of diarrheal illness. At least 5 categories of diarrheagenic E. coli (DEC) are recognized, namely enterotoxigenic E. coli (ETEC), enteropathogenic E. coli (EPEC), enteroinvasive E. coli (EIEC), enteroaggregative E. coli (EAEC), and enterohemorrhagic E. coli (EHEC). Due to the need for costly and labor-intensive diagnostic procedures, identification of DEC is difficult at standard laboratories. Therefore, the epidemiology of DEC infections remains obscure in Taiwan. Recently, polymerase chain reaction (PCR) or dot blot has been used for genetic detection of DEC. In this study, we analyzed 150 E. coli isolates from diarrheal stools of children under 5 years old. The PCR tests detected 5 ETEC (3.3%), 6 EPEC (4%), 4 EIEC (2.7%), and 13 EAEC (8.7%) isolates. No EHEC was detected. Dot blot and sequence analysis were used to confirm the results of PCR. The cellular fatty acid (CFA) profiles from E. coli isolates were also analyzed. Comparison of CFA composition revealed minor variation in the percentage of each fatty acid detected among DEC isolates of ETEC, EPEC, EIEC and EAEC, but did not provide enough evidence for differentiating between categories of DEC by CFA profiles alone.

The annual incidence of meningococcal disease (meningitis and septicaemia) in Taiwan was 0·94/105 population in 1953. It then declined to below 0·001 from 1980 to 1987, and re-emerged in 2000 with a rate of 0·07/105 population. In 2001 there was a further increase in incidence (43 cases, 0·19/105). Of 43 isolates of Neisseria meningitidis available for this study, including 41 from patients treated in 2001, three (7·0%) were penicillin insensitive (MIC [ges ]0·12 μg/ml), though all were β-lactamase negative; 16 (37·2%) were resistant to trimethoprim–sulphamethoxazole sulphamethoxazole (MIC [ges ]4/76 μg/ml). Serogrouping and genotype analysis revealed nine domestic clones. None of the 43 patients had any relationship (travel or contact history) with the 2000 or 2001 Hajj pilgrimage. Epidemiological information and typing results suggested wide dissemination of a limited number of domestic clones of N. meningitidis, manifesting as serogroups W-135, B and Y. Two clones of serogroup W-135 involved in the outbreak were genetically distinct from the 2000 or 2001 Hajj-related W-135 clone.

Among 55 preserved isolates collected in northern Taiwan from 1999 through 2003 ciprofloxacin resistance (minimum inhibitory concentration =1 mg/mL) was found in 1 (25%) of 4 isolates obtained in 1999–2000 and in 27 (93.1%) of 29 isolates obtained in 2003. Pulsed-field gel electrophoresis analysis indicated that several clones predominated among the ciprofloxacin-resistant isolates. (excerpt)

The feasibility of sequence analysis of the 16S-23S ribosomal DNA (rDNA) intergenic spacer (ITS) for the identification of clinically relevant viridans group streptococci (VS) was evaluated. The ITS regions of 29 reference strains (11 species) of VS were amplified by PCR and sequenced. These 11 species were Streptococcus anginosus , S. constellatus , S. gordonii , S. intermedius , S. mitis , S. mutans , S. oralis , S. parasanguinis , S. salivarius , S. sanguinis , and S. uberis . The ITS lengths (246 to 391 bp) and sequences were highly conserved among strains within a species. The intraspecies similarity scores for the ITS sequences ranged from 0.98 to 1.0, except for the score for S. gordonii strains. The interspecies similarity scores for the ITS sequences varied from 0.31 to 0.93. Phylogenetic analysis of the ITS regions revealed that evolution of the regions of some species of VS is not parallel to that of the 16S rRNA genes. One hundred six clinical isolates of VS were identified by the Rapid ID 32 STREP system (bioMérieux Vitek, Marcy l'Etoile, France) and by ITS sequencing, and the level of disagreement between the two methods was 18% (19 isolates). Most isolates producing discrepant results could be unambiguously assigned to a specific species by their ITS sequences. The accuracy of using ITS sequencing for identification of VS was verified by 16S rDNA sequencing for all strains except strains of S. oralis and S. mitis , which were difficult to differentiate by their 16S rDNA sequences. In conclusion, identification of species of VS by ITS sequencing is reliable and could be used as an alternative accurate method for identification of VS.

The association of Streptococcus bovis biotypes with types of clinical infection and underlying malignancies has rarely been reported in Taiwan. The aim of this study was to characterize the clinical features and microbiological characteristics of patients with S. bovis bacteremia.From January 1992 to December 2001, 62 patients with S. bovis bacteremia were treated at National Taiwan University Hospital. Their demographic characteristics, clinical features, results of imaging studies, pathological findings, and laboratory data were retrospectively analyzed. Antimicrobial susceptibilities were determined using the agar dilution method and biotypes were determined using the API 20 Strep system.The majority of cases (76%) occurred during the 1996-1997 and 1999-2000 periods. Thirty five patients were male, and the mean age of the 62 patients was 61 years. Underlying diseases included malignancies (40%), cardiac diseases (27%), diabetes mellitus (24%), and liver cirrhosis (21%). Fifty two percent (n = 32) of patients presented with primary bacteremia and 24% (15) with definite or possible infective endocarditis. Thirteen percent (8) presented with hepatobiliary infections (acute cholecystitis and biliary tract infection). Ten patients (16%) had polymicrobial bacteremia. All of the concomitant pathogen(s) were Gram-negative rods, among which Escherichia coli predominated. The mortality rate on day 30 of illness was 21%. High Acute Physiology and Chronic Health Evaluation (APACHE) II score on the day of positive blood culture was associated with high mortality. Among the 19 patients (31%) who underwent colonoscopy, 9 (47%) had colonic lesions (tubular adenomas or carcinomas). Of the 26 patients (41%) who underwent echocardiography, 14 (54%) had vegetation in the valves. Of the 47 S. bovis isolates examined for biotypes, 37 (79%) were biotype II (29 of biotype II/2 and 8 of biotype II/1) and 10 (21%) were biotype I. The majority of isolates causing primary bacteremia (92%), hepatobiliary infections (100%) and primary bacterial peritonitis (100%) were biotype II, while 67% of isolates associated with infective endocarditis were biotype I. All isolates were susceptible to penicillin.Infective endocarditis should be highly suspected in patients with bacteremia due to S. bovis biotype I. Investigations for intra-abdominal foci other than the colon should be undertaken in patients with bacteremia caused by S. bovis biotype II. Due to the increasing number of S. bovis bacteremia patients at the hospital and unknown origins of about 50% of bacteremia cases, the need for colonoscopy and echocardiography in each case and biotyping of each blood isolate should be emphasized.

Data obtained from 1996 to 2002 on 13 patients with Rhizobium radiobacter infections were analyzed. Ten patients (76%) had underlying hematological malignancy or solid-organ cancer. Six patients (46%) had febrile neutropenia during the course of R. radiobacter infection. The majority (54%) of infections were catheter-related bacteremia, and 92% of infections were hospital acquired. All the patients survived. Eighteen isolates were recovered from the 13 patients, and each isolate was susceptible to cefepime, piperacillin-tazobactam, carbapenems, and ciprofloxacin. The pulsed-field gel electrophoresis profiles differed among the isolates recovered from different patients, indicating the absence of nosocomial spread of the organism.

From January 1993 to December 2002, 28 patients with nutritionally variant streptococci (NVS) infections were treated at a university hospital in Taiwan. Twelve (43%) of these patients had various underlying malignancies, and 7 (25%) had underlying valvular heart diseases. Nine patients (32%) had infective endocarditis, and 9 (32%) had primary bacteremia. The deaths of 7 patients (25%) were directly related to NVS infection. Among the 28 isolates recovered from these patients, 50% were not susceptible to penicillin, 33% were not susceptible to cefotaxime, and 93% were not susceptible to azithromycin.

We describe a central venous catheter-related (Port-A-Cath; Smiths Industries Medical Systems [SIMS] Deltec, Inc., St. Paul, Minn.) infection caused by Rhodotorula glutinis in a 51-year-old man with nasopharyngeal carcinoma. He was treated with fluconazole for 8 weeks and had the catheter removed. Two isolates of R. glutinis recovered from blood specimens (one obtained via peripheral veins and one via the catheter) before administration of fluconazole and one recovered from the removed catheter 17 days after initiation of fluconazole therapy exhibited high-level resistance to fluconazole (MICs, >256 μg/ml). These three isolates were found to belong to a single clone on the basis of identical antibiotypes determined by the E test (PDM Epsilometer; AB Biodisk, Solna, Sweden) and biotypes determined by API ID32 C (bioMerieux, Marcy I'Etoile, France) and their identical random amplified polymorphic DNA patterns.

The incidence of nosocomial Candida fungemia increased 36-fold from 1981 (0.8/10,000 discharges) to 2000 (28.8/10,000 discharges) at the National Taiwan University Hospital, a 2000-bed teaching hospital in northern Taiwan. To understand the current status of resistance to available antifungal agents among Candida species causing invasive infections, the in vitro susceptibilities of 222 isolates (collected from July, 1999-June, 2001) were determined. Among all of the Candida species tested, 6% and 7% were resistant to fluconazole and itraconazole, respectively. The MIC90 values of voriconazole and amphotericin B were 0.5 and 1 microg/ml, respectively, although some isolates of C. krusei (amphotericin B and voriconazole MIC,64 microg/ml) and C. tropicalis and C. glabrata (voriconazole MICs,64 microg/ml) were less susceptible to voriconazole or amphotericin B. About one-half of the C. glabrata isolates belonged to susceptible dose-dependent (SDD, 36%) or resistant (12%) categories for fluconazole and 96% belonged to SDD (56%) or resistant (40%) category for itraconazole. When compared with fluconazole susceptibility data of blood Candida isolates recovered from patients treated at the same hospital (NTUH) from two different time periods (January, 1994, to June, 1995, and January, 1997, to June, 1999 described in previous reports), the incidence of increased susceptibility of non-krusei Candida isolates to fluconazole was evident. This trend of increasing susceptibility for fluconazole did not correlate to the increasing use of this agent in the hospital. None of the random amplified polymorphic DNA patterns generated by arbitrarily primed PCR using four random oligonucleotide primers for 14 isolates, which exhibited fluconazole MICs ofor = 16 microg/ml, were identical, indicating an absence of clonal dissemination among these isolates in the hospital.

Stenotrophomonas maltophilia, a major pathogen causing nosocomial infection, is inherently resistant to multiple antimicrobial agents. Evaluation of the effectiveness of recommended therapeutic options for S. maltophilia infections is crucial, particularly in areas with high antimicrobial resistance in this nosocomial pathogen.The in vitro activities of ceftazidime (CAZ), ticarcillin-clavulanate (TIM), amikacin (AN), ciprofloxacin (CIP), and trimethoprim-sulfamethoxazole (TMP-SMZ) against 102 clinical isolates of S. maltophilia collected from January 1998 to December 1999 at a university hospital were evaluated. The disk diffusion and agar dilution susceptibilities of individual agents against these isolates were determined concomitantly. Errors between results obtained by the two methods were identified based on the guidelines for Acinetobacter species provided by the National Committee for Clinical Laboratory Standards. Activities of three two-drug combinations (AN + CIP, CAZ + CIP, and TIM + TMP-SMZ) against 32 of these isolates were analyzed using the checkerboard synergy test.Among the agents tested, TMP-SMZ was the most active against S. maltophilia (83.3% susceptible), followed by CIP (63.7%), CAZ (39.2%), TIM (36.2%), and AN (20.5%). Errors (very major and major) between the results obtained by the disk diffusion and agar dilution methods occurred at a high frequency for AN (15% and 3%), CAZ (8% and 6%), and CIP (3% and 3%). Synergy or partial synergy of antimicrobial agent combinations was detected predominantly with CAZ + CIP (81.3%) and TIM + TMP-SMZ (84.4%) but not with AN + CIP (37.5%). No antagonism was detected with any drug combinations.The dilution method is preferable to the disk diffusion method for susceptibility testing of S. maltophilia isolates, particularly for testing with AN, CAZ, and TIM, which have considerable error rates between the results obtained by the two methods. The findings from the synergy test suggest that TIM + TMP-SMZ and CAZ + CIP combinations are the treatments of choice for infections caused by S. maltophilia.

Susceptibilities to 13 antimicrobial agents were determined by measurement of MICs for 60 isolates of Streptococcus bovis from blood cultures. Thirty-eight isolates (63.3%) had high-level resistance to erythromycin (MICs, ≥128 μg/ml). Among the 38 erythromycin-resistant strains, 21 isolates (55%) had inducible resistance to macrolides-lincosamides-streptogramin B (iMLS isolates) and 17 (45%) had constitutive resistance to macrolides-lincosamides-streptogramin B (cMLS isolates). Tetracycline resistance was also found among all of the erythromycin-resistant strains. None of the strains displayed resistance to penicillin, chloramphenicol, or vancomycin. Detection of erythromycin resistance genes by PCR and sequencing indicated that all 17 cMLS isolates were positive for the ermB gene and that 7 of 21 iMLS isolates carried the ermB gene and the remaining 14 iMLS isolates carried the ermT gene. Sequence analysis of amplified partial ermB fragments (594 bp) from S. bovis isolates revealed a 99.8% nucleotide identity and a 100% amino acid homology compared with the sequences from gene banks. The sequences of amplified fragments with primers targeted for ermC were shown to be very similar to that of ermGT ( ermT ) from Lactobacillus reuteri (98.5% nucleotide identity). This is the first report to describe the detection of the ermT class of erythromycin resistance determinants in S. bovis . The high rate of inducible erythromycin resistance among S. bovis isolates in Taiwan was not reported before. The iMLS S. bovis isolates were shown to be heterogeneous by randomly amplified polymorphic DNA analysis. These results indicate that the prevalence of inducible erythromycin resistance in S. bovis in Taiwan is very high and that most of the resistant strains carry the ermT or the ermB gene.

We report a case of persistent bacteraemia caused by a single clone of Burkholderia cepacia with unusual characteristics. Six isolates of B. cepacia were recovered from a patient with acute myeloid leukaemia and chemotherapy-induced neutropenia within a 3-week period. All six isolates were initially incompletely identified as B. cepacia with the API 20NE system. The further use of cellular fatty acid analysis and PCR-restriction fragment length polymorphism of the 16S rDNA confirmed the identification. These isolates also displayed an identical but unusual antibiotype. The identical cellular fatty acid profiles and genomic typing generated by random amplified polymorphic DNA identified theseisolates as derivatives of a single strain.

We describe a 66-year-old woman with infective endocarditis due to Cardiobacterium hominis whose condition, complicated by severe aortic regurgitation and congestive heart failure, necessitated aortic valve replacement despite treatment with ceftriaxone followed by ciprofloxacin. The blood isolate of C. hominis produced β-lactamase and exhibited high-level resistance to penicillin (MIC, ≧256 μg/ml) and reduced susceptibility to vancomycin (MIC, 8 μg/ml).

From January 1996 to December 1997, 200 isolates of Streptococcus pneumoniae recovered from 200 patients treated at National Taiwan University Hospital were serotyped and their susceptibilities to 16 antimicrobial agents were determined by the agar dilution method. Sixty-one percent of the isolates were nonsusceptible to penicillin, exhibiting either intermediate resistance (28%) or high-level resistance (33%). About two-fifths of the isolates displayed intermediate or high-level resistance to cefotaxime, ceftriaxone, cefepime, imipenem, and meropenem. Extremely high proportions of the isolates were resistant to erythromycin (82%), clarithromycin (90%), and trimethoprim-sulfamethoxazole (TMP-SMZ) (87%). Among the isolates nonsusceptible to penicillin, 23.8% were resistant to imipenem; more than 60% displayed resistance to cefotaxime, ceftriaxone, cefepime, and carbapenems; 96.7% were resistant to erythromycin; and 100% were resistant to TMP-SMZ. All isolates were susceptible to rifampin and vancomycin. The MICs at which 50% and 90% of the isolates were inhibited were 0.12 and 1 μg/ml, respectively, for cefpirome, and 0.12 and 0.25 μg/ml, respectively, for moxifloxacin. Six serogroups or serotypes (23F, 19F, 6B, 14, 3, and 9) accounted for 77.5% of all isolates. Overall, 92.5% of the isolates were included in the serogroups or serotypes represented in the 23-valent pneumococcal vaccine. The incidence of macrolide and TMP-SMZ resistance for S. pneumoniae isolates in Taiwan in this study is among the highest in the world published to date.

From December 1997 to March 1998, 25 methicillin-resistant Staphylococcus aureus (MRSA) isolates exhibiting negative Staphylase (Oxoid Ltd., Basingstoke, England) reactions were identified from various clinical specimens from 13 patients in six intensive care units (ICUs) or in wards following a stay in an ICU at the National Taiwan University Hospital. The characteristics of these isolates have not been previously noted in other MRSA isolates from this hospital. Colonies of all these isolates were grown on Trypticase soy agar supplemented with 5% sheep blood and were nonhemolytic and unpigmented. Seven isolates, initially reported as Staphylococcus haemolyticus (5 isolates) and Staphylococcus epidermidis (2 isolates) by the routine identification scheme and with the Vitek GPI system (bioMerieux Vitek, Inc., Hazelwood, Mo.), were subsequently identified as S. aureus by positive tube coagulase tests, standard biochemical reactions, and characteristic cellular fatty acid chromatograms. The antibiotypes obtained by the E test, coagulase types, restriction fragment length polymorphism profiles of the staphylococcal coagulase gene, and random amplified polymorphic DNA patterns generated by arbitrarily primed PCR of the isolates disclosed that two major clones disseminated in the ICUs. Clone 1 (16 isolates) was resistant to clindamycin and was susceptible to trimethoprim-sulfamethoxazole (TMP-SMZ) and was coagulase type II. Clone 2 (eight isolates) was resistant to clindamycin and TMP-SMZ and was coagulase type IV. These two epidemic clones from ICUs are unique and underline the need for caution in identifying MRSA strains with colonial morphologies not of the typical type and with negative Staphylase reactions.

Neisseria sicca is rarely associated with clinical infections and to the authors' knowledge this organism has not been reported as a causative agent of infected biloma (liver abscess). A case of a diabetic man with infected biloma due to N. sicca after repeated transcatheter arterial embolization for hepatocellular carcinoma is reported. The patient was successfully treated with intravenous cefotaxime and metronidazole. The biochemical profile and 16S rRNA gene partial sequencing results of the isolate were in agreement with those of N. sicca.

The in-vitro susceptibilities of 13 antimicrobial agents were determined for 207 isolates of viridans group streptococci recovered from patients with significant infections in Taiwan during 1995 and 1997. Variable degrees of susceptibility existed among nine species. High-level penicillin resistance (MIC > or = 4.0 mg/L) was found most frequently in Streptococcus oralis (35%), followed by Streptococcus mitis (20%) and Streptococcus salivarius (8%). However, S. salivarius showed the lowest rate of susceptibility to penicillin (50%). Macrolide resistance also occurred most frequently in S. oralis isolates (55%) but in none of Streptococcus mutans. Penicillin and macrolides tended to be less active against isolates recovered from non-invasive sites than against those isolated from invasive sites. Imipenem was the most active beta-lactam against penicillin-resistant isolates. Ofloxacin, vancomycin and teicoplanin showed good in-vitro activity against all isolates, with MIC90s of 2, 1 and 0.25 mg/L, respectively. None of these isolates displayed high-level resistance to gentamicin and most isolates were susceptible to chloramphenicol. These results indicate the species-related variability of susceptibility, especially to penicillin, macrolides and tetracycline. In addition to S. mitis, S. oralis also displayed high rates of resistance to penicillin and macrolides. The difference in susceptibilities between species of viridans streptococci indicates the importance of accurate identification and the need for continuing surveillance of antimicrobial resistance.

Long-term colonization of various body sites with a multidrug-resistant Pseudomonas aeruginosa clone (resistant to piperacillin, cefoperazone, ceftazidime, aztreonam, imipenem, cefepime, cefpirome, ofloxacin, ciprofloxacin, minocycline, and aminoglycosides) with subsequent severe infections in burn patients has not been reported previously. Thirty-nine isolates of multidrug-resistant P. aeruginosa (resistant to ceftazidime and at least three of the agents listed above) recovered from various clinical samples from three patients in an intensive care burn unit from April 1997 to May 1997 and seven preserved isolates recovered from six patients in other medical wards at National Taiwan University Hospital from April 1996 to May 1997 were studied for their epidemiological relatedness. The epidemic could be attributed to a multidrug-resistant P. aeruginosa clone belonging to serogroup O:F (serogroup O:4) by means of antimicrobial susceptibility testing, O serogrouping, and analysis of the randomly amplified polymorphic DNA patterns generated by arbitrarily primed PCR of the isolates. The epidemic strain persisted in the three patients for weeks to months; in the meantime, these patients had received multiple antimicrobial agents for the management of intervening episodes of invasive infections (bacteremia, ventilator-associated pneumonia, and/or catheter-related sepsis) caused by this strain, as well as concomitant infections due to other organisms. The strain had been isolated only once previously, from a burn patient who was on the unit in December 1996. The present report, describing a small outbreak due to P. aeruginosa , documents the fact that a single clone of multidrug-resistant P. aeruginosa can cause long-term persistence in different body sites of burn patients and that the colonization can subsequently result in various severe infections.

We describe herein a recurrent catheter-related (Port-A-Cath; Smiths Industries Medical Systems [SIMS] Deltec, Inc., St. Paul, Minn.) infection caused by multidrug-resistant Mycobacterium chelonae with two colonial morphotypes in a 53-year-old woman with gastric adenocarcinoma. Four isolates recovered from this patient within a 3-month period were found to belong to a single clone on the basis of the isolates’ identical antibiotypes as determined by the E test and their identical random amplified polymorphic DNA patterns.

From January 1995 to September 1996, 14 isolates of Sphingomonas paucimobilis, including 11 from clinical specimens from six patients with nosocomial infection and three from environmental sources, were collected. Two of the six patients had intravascular catheter-related bacteremia and one each had bacteremic biliary tract infection, urinary tract infection, ventilator-associated pneumonia, and wound infection. The S. paucimobilis isolates were identified according to biochemical profiles established with use of the API 20NE system and Vitek GNI card and the characteristic cellular fatty acid chromatogram. Ten biotypes, 11 antibiograms (by the Etest), and 12 random amplified polymorphic DNA (RAPD) patterns (by arbitrarily primed polymerase chain reaction) were identified. The identical biotype, antibiogram, and RAPD pattern of the two isolates (one each from blood and bile) from a patient with biliary tract infection indicated the invasiveness of the organism. Two patients with intravascular catheter-related bacteremia had isolates of this organism repeatedly recovered, and these isolates had heterogeneous RAPD patterns. The present study highlights the wide distribution in hospital environments of various clones of S. paucimobilis, which may cause recurrent infections by a single strain or several episodes of infection due to two or more clones of this organism in hospitalized patients.

From October 1995 to February 1997, 13 isolates of Aeromonas species were recovered from four patients treated at National Taiwan University Hospital (Taipei). One of the patients, a diabetic, had simultaneous Aeromonas veronii biotype veronii bacteremia and A. veronii biotype sobria urinary tract infection. Seven weeks after the episode, the patient had necrotizing fasciitis due to A. veronii biotype veronii. The other three patients all had underlying hepatobiliary malignancies complicated by obstructive jaundice, and all underwent percutaneous transhepatic cholangiographic drainage. These three patients had multiple isolates of Aeromonas species (A. hydrophila and/or A. caviae) recovered from samples of blood or bile or from catheter insertion sites. All isolates were identified on the basis of the results of extended biochemical tests as well as characteristic cellular fatty acid profiles. The results of genotyping generated by arbitrarily primed polymerase chain reaction and of susceptibility testing showed that these Aeromonas species were pathogens that caused indwelling device-related infections and that the organisms could persist for long periods, with subsequent recurrence of severe infection. Concomitant infection due to more than one Aeromonas species or caused by polyclonal A. hydrophila or A. veronii biotype veronii was also documented.

Two isolates of serum-susceptible Campylobacter coli were recovered in a 7-day interval from blood from a patient with hepatocellular carcinoma and liver cirrhosis whose peritoneal-caval (Denver's) shunt malfunctioned. Identical random amplified polymorphic DNA fingerprints, cellular fatty acid chromatograms, and antibiograms of the two isolates indicate that C. coli has the ability to cause catheter-related bacteremia following its colonization of the catheter.

An outbreak of scarlet fever involving 12 children occurred at a hospital day care centre from February to March 1996. Twenty-five throat isolates of Streptococcus pyogenes (GAS, group A streptococcus) available from 24 children, including 10 children with scarlet fever and 14 asymptomatic carriers, and one asymptomatic staff member were studied for the presence of genes encoding streptococcal pyrogenic exotoxin types A (speA), B (speB), and C (speC) and for protease activity. Antimicrobial susceptibilities using the E-test, cluster analysis by cellular fatty acid composition and random amplified polymorphic DNA (RAPD) patterns by means of arbitrarily-primed polymerase chain reaction (APPCR) of the isolates were performed to investigate the outbreak. Only one isolate from an asymptomatic child possessed the speA gene. All isolates possessed the speB gene and 24 (96%) isolates were positive for the speC gene. There was no difference in protease activity between isolates from children with scarlet fever and from asymptomatic carriers. Thirteen isolates (10 recovered from children with scarlet fever, two from asymptomatic children, and one from the staff member) were considered to be the same strain according to the identical antimicrobial susceptibility profile and RAPD patterns and were also considered to be similar by cluster analysis of fatty acid composition. These findings suggest that the outbreak was caused by a unique clone of GAS. We conclude that RAPD typing and cluster analysis by cellular fatty acids composition both provide a powerful tool for epidemiological investigation of GAS infections.

Flavimonas oryzihabitans is rarely reported as a pathogen in humans. Twelve cases of F. oryzihabitans bacteremia were diagnosed at National Taiwan University Hospital over a 3-year period. The clinical features of these patients were analyzed, and antimicrobial susceptibilities and random amplified polymorphic DNA (RAPD) patterns of the 12 isolates were studied. Among these 12 patients, eight (67%) had underlying neoplastic diseases and all acquired F. oryzihabitans bacteremia while hospitalized. The clinical syndromes included primary bacteremia in 5 patients (42%), biliary tract infection in 3 (25%), and peritonitis, subdural empyema, infusion-related bacteremia, and pneumonia in 1 each. Polymicrobial bacteremia or concomitant fungemia was seen in three patients (25%). All the patients survived after antibiotic treatment. All isolates were susceptible to piperacillin, third-generation cephalosporins, aminoglycosides, and quinolones but resistant to cephalothin, cefuroxime, and trimethoprim. Susceptibility to aztreonam was variable (25%). The RAPD patterns differed among the isolates, indicating the epidemiological unrelatedness of these infections. F. oryzihabitans should be included as an etiology of severe nosocomial infection in patients with underlying debilitating diseases.

Arcobacter cryaerophilus group 1B, a gram-negative, curved or helical bacillus primarily known as a bovine and porcine pathogen, was isolated from the blood of a uremic patient with hematogenous pneumonia. The patient was treated successfully with ceftizoxime and tobramycin.

To our knowledge, this is the firstreport of a linezolid-resistant Enterococcus faecium strainisolated in Taiwan.The 51-year-old woman developed disseminated Mycobacter-ium fortuitum infection and presented with fever, lymphadenopa-thy and bacteraemia in December 1999. During the 9 months oftreatment course in hospital and in outpatient clinic, she receivedamikacin, ciprofloxacin, doxycycline, clarithromycin, or rifabu-tin. Splenic abscess, granulomatous hepatitis, and generalizedlymphadenopathy developed in September 2000. Culture of liverbiopsy and bone marrow both yielded Mycobacterium aviumcomplex (MAC). She was treated with clarithromycin, ciproflox-acin and rifampicin for 6 months followed by ciprofloxacin andclarithromycin for 1 year.In December 2002, the patient was admitted due to fever andabdominal pain for 2 weeks. Abdominal sonography showedmultiple lymph nodes over the mesenteric and aortic areas.Blood cultures and bone marrow cultures carried out during theadmission all yielded MAC. During the following 20 months ofhospitalization, progressive osteomyelitis developed over the cer-vical and thoracic spine complicated with retropharyngeal andprevertebral abscess, quadriparesis, diffuse lymphadenopathy,granulomatous hepatitis with hepatic calcification, and empyemathoracis due to MAC. Several episodes of nosocomial pneumoniaalso occurred and necessitated ventilator support. Her conditionwas refractory to long-term treatment with many antimycobacter-ial agents, including ciprofloxacin (1000mg every day, 1030days), clarithromycin (1000mg every day, 1020 days), azithro-mycin (500mg every day, 188 days), imipenem (2g every day170 days), amikacin (500mg, every two days, 145 days), clofazi-mine (100mg every day, 175 days), mefloquine (500mg thriceweekly, 149 days), linezolid (600mg every 12h, 155 days), andinterferon-g (75mg thrice weekly) for 2 months (Figure 1).

to invasive disease and rheumatic heart disease and mainly amongst the young and elderly populations. Population-based studies have described the epidemiology and clinical features of GAS diseases ranging from classic sore throat to severe life-threatening infections, such as septicaemia, streptococcal toxic shock syndrome (STSS) and necrotising fasciitis. GAS epidemiology varies with time and is dependent upon geographic location and socio-economic conditions. Timely monitoring of incidence, mortality and microbiological characteristics is essential to identify changes in disease patterns and emergence of hypervirulent strains, providingopportunities for alerts to be cascaded to frontline medical staff to facilitate early diagnosis, prompt initiation of life-saving therapy and inform the development of guidelines for control and management. The organism possesses numerous cell surface proteins that play a key role in host–bacteria relationships such as virulence and or adherence and form the basis of the GAS typing scheme. These proteins also represent choice candidates for vaccine developments. M-protein is a surface protein encoded by the emm gene which acts as a major virulence factor. Emm -typing is the molecular gold standard and there are currently more than 200 emm types described worldwide. More recently the application of novel comparative genomics has contributed towards our knowledge of the mechanisms underlying GAS pathogenesis. The information gained from current whole genome sequencing studies could translate into improved diagnostics; identification of novel molecular markers and potential predictors for the iGAS disease process and new targets for therapeutic drugs and vaccines.